Voltage regulator



June 29, 1937.

A. A. EMLEN El AL VOLTAGE REGULATOR 4 Sheets-Sheet 1 Filed De c. 26.1935 INVENTORS L dmwvil wz/iz ZZ e E-Lundgm ATTORNEYv June 29; 1937.EMLEN 2,085,255

VOLTAGE REGULATOR IN V EN TO R S uqzzdn urfi 272214 ATTORNEY June 29,1937. A. A. EMLEN tr AL 2,035,255

VOLTAGE REGULATOR "Filed Dec. 26, 1935 4 Sheets-Sheet 3 PRIMARYINVENTORS 9 wdregghn BY We uwozg nfizp ATTORNEY PRKMARY A. A. EMLEN ErAL 5 VOLTAGE REGULATOR Filed Dec. 26, 1935 4 Sheets-Sheet 4 PRIMARY ILOAD Q I ATTORNEY Patented June 29, 1937 VOLTAGE REGULATOR Andrew A.Ernlen, Roselle, and Tage H. Lundgren, Irvington, N. J., assignors toAmerican Transformer Company, Newark, N. J.

Application December 26; 1935, Serial No. 56,216

20 Claims.

This invention relates to the construction of a voltage regulatorparticularly adapted for use 10 to a collector of the commutator'typehaving a brush mounted forrotation about the periphery of the collector.In general, such a voltage regulator is described in Hunter Patents2,014,570, issued September 17, 1935; and 1,993,007, issued March 5,1935, in which are shown certain mechanisms for reversing the brushrotating around the collector after the brush has reached the limit ofits travel there-around; that is, substantially one full revolution, atthe end of which time, the Geneva gear arrangement actuates one of theswitches having contacts connected to the coarse taps of one of thetransformer windings.

It is the principalv object of our invention to simplify theconstruction and thereby reduce the cost of operation and maintenance ofthe regulator.

In particular, our invention is directed to entirely eliminating themechanism used for reversing the direction of rotation of the collectorbrush at the end of'each revolution thereof.

Our improvements will be readily understood by reference to theaccompanying drawings, in

which: I I

Figure 1 is an elevational view on a reduced scale, of one type ofregulator to which our invention is applied.

Figure 2 is a view looking from right to left of Figure 1.

Figure 3 is a top view of Figure 1.

Figure 4 is a view on the line 44 of Figure 5.

Figure 5 is a part-sectionaland part-elevational view through theregulator, without any of the connections being shown, these connections being omitted for the purpose of clarity, since they are moreclearly shown in the diagrammatic forms of Figures 6, '7, and 8.

Figure 6 is a diagram of the circuit connections, showing one form inwhich our invention may be applied.

Figure '7 is a wiring diagram of another form which our invention maytake.

Figure 8 is a wiring diagram of a further modified form.

In the Various views, wherein like numbers refer to corresponding parts,I illustrates, generally, a casing supported by a framework 2 having endclosure plates 3 and 4. Adjacent the top closure plate 4, is a plate 5,preferably of strong insulating material, which carries two sets ofrotary switch contacts designated, a1ternately,- 5 a to h inclusive,corresponding to the diagram shown in Figure '7.

Cooperating with these contacts are two switch levers 6 and I which arecarried on coupling members 8 and 9 of insulating material opera- 10tively connected to bearing pins ill. and H, the pin I! having abearingin the top plate 4. One of the bearing pins ll, for one of the switches,carries a Geneva gear l2, while the corresponding pin for the otherswitch carries a Geneva gear i3, both of which are adapted to beoperated by a gear-i4 having a single tooth S5. The gear Hi isoperatively connected to a main drive shaft l6 carrying a gear lladapted to mesh with the pinion l8 carried on an operating shaft I9which, as shown, is adapted to be manually operated by the handwheel253, although it is to be understood that the regulator may beoperatedautomatically as shown and described in Hunter Patent 1,993,007.

Within the framework 2 of the regulator is carried a main transformer 2ihaving a series of coarse taps connected to the switch contacts of therotary switches 5 and l' as shown in the wiring diagrams. A collectortransformer 22 is also carried by the framework 2 and has a series offine taps connected to the various bars of the commutator type collector23. Cooperating with the collector 23 is a pair of brushes 24 carried ona stud 25 attached to a flange 26 andprefer- I ably integral with a slipring 21. While we have shown two brushes 2% in cooperation with thecollector 23, we have referred in the claims, broadly, to a brush. Theslip ring 2'?! is fastened to an insulator 28 in any satisfactory manneras by a bolt 29 engaging a stud or projection 3G within the interiorportion of the ring 27. The lower end of the shaft it has a bearingwithin a gland 3! at one end of the collector 23.

The insulator 28 is fastened to the shaft I6 in any satisfactory manneras by a pin 32 and a clamping collar 33. Contacting with the slip ring21, is a brush 34 carried on a stud 35 which is attached to a metalplate 36, which in turn is fastened by a bolt or stud 31 to an insulator38 of strong material, which in turn is fastened to a frame member 39 byany satisfactory means as by one or more bolts or studs 10.

The shaft I6 is threaded intermediate its ends at 4|, and on thisthreaded portion are adjustably positioned, by set screws 42, a pair ofnuts 43 and 44. Between the nuts 43 and 44, a stop member 45 ispositioned, it being threaded to engage the threads 4| on the shaft "3.The 5 outer end ofthe member 45 engages a guide and support member 46which is slotted between the dotted lines 41 to receive the end of thearm 45,

thereby preventing it from rotating about the shaft 4|, but allowing themember 45 to travel up and down on the shaft as the shaft I6 is rotated.This travel of the stop member 45 is adjusted by the nuts 43 and 44, wasto allow the brush 24 to travel around the collector 23 continuously inthe same direction as many times as there are steps of the rotaryswitches 5 and I. By way of illustration and reference to Figures 4 and'7, the switch 6, while having fourcontacts, has three steps; andlikewise, the

switch 1 has three steps so that the brush 24 will rotate around thecollector 23 three complete times before it is stopped by the member 45engaging either the nut 43 or the nut 44. In

other words, after the rotary switches have been moved throughout theircomplete range in 25 one direction, the regulator is locked againstfurther movement in that particular direction. Then the regulator can beoperated in reverse direction to the full limit as provided by thecorresponding stop devices described.

Prom the above, it is seen that the reversing mechanism for reversingthe direction of rotation of the brush 24 about the collector 23, asrequired in Hunter Patent 1,993,007, is entirely eliminated, but inmaking this elimination, special provision must be made in thecommutator to allow a time interval for the switches 6 and I to beoperated so that they will be on contact, whereby the load circuit willnever be opened. This arrangement is accomplished in Figure 6, byproviding two special commutator bars 48 and 49 of sufficient width toaccomplish the desired purpose, which will be readily understood by abrief description of the operation of the regulator as shown in Figure6.

In this diagrammatic arrangement, the brush 24 is shown in contact withthe special extrawidth commutator bar 48, the switches 8 and I being onthe contacts a and a, it being understood that the contacts associatedwith the switches 6 and I are connected to coarse taps on thetransformer 2|. As the brush 24 rotates around the collector 23 inclockwise direction, the various fine taps from the transformer winding22 are encountered to regulate the voltage in accordance with thewell-known way as set forth in said Hunter patents, so furtherdescription does not appear to be necessary. When the brush 24 reachesthe bar 49, the mechanism and gearing are arranged so that the switchlever 8 moves from a to b, the width of the bar 49 being sufiicient toallow for this switching to take place, so that the load circuit willnot be opened. After the brush moves from 49 to 48 and is on 48, theswitch I is moved from a to b. Because of the continuous rota tion ofthe brush 24 around the commutator, the slip ring 21 must be used inorder to carry the current through the brush 24 out to the load circuit.

We have shown in Figure 6, the switches 6 and I each having eightcontacts, but there may be any number of contacts desired. For example,in Figure 7 only four contacts for each switch are illustrated. In thearrangement of Figure 7, the collector 23 is a little difierentlyconstructed than in Figure 6. In this arrangement the wide bars 48 and49 are diametrically disposed so that the brush 24 covers all of thefine taps during one-half revolution, and then while it is on one of thewide bars, for example 49, one of the switches is operated and the brush24 contacts with bars on the opposite sides of the commutator, which arecross-eonnected to the corresponding bars on the opposite side of thecollector, one set of the bars being connected to the fine taps of thetransformer 22.

A modification of Figure 7 is shown in Figure 8, wherein the winding 22is split into two windings 50 and 5|, which arrangement does notrequire.crossconnecting of the commutator bars as in Figure '7. Asheretofore explained, however, the adjustment of the stop member 45 onthe shaft l6 controls the number of times the brush 24 travels aroundthe collector, or in accordance with the number of. steps or movementrequired by the switches 6 and 1.

From what has been said, it will be seen that our arrangement does awaywith the more or less complicated reversing mechanism required where thebrush 24 has to be reversed in direction at the end of each revolutionaround the commutator.

While the various details of construction may be varied, we have shown apractical illustration of the application of our invention.

What we claim is:

1. In a voltage regulator including; at least a pair of separatetransformer windings, one having coarse taps and the other fine taps,the coarse taps from one winding being interconnected to the otherwinding through a pair of independently operable switches with means foroperating the switches alternately in steps so the circuit between thewindings, including the load circuit, is never opened, a 'collector ofthe commutator type having bars connected to the fine taps of said otherwinding, a brush adapted to be continuously connected to a circuit whosevoltage is to be regulated, said brush being mounted for rotation aroundsaid collector, characterized in that the electrical connections betweensaid windings, switches and collector are such that the brush on thecollector can be rotated continuously in the same direction around thecollector throughout the range of movement of said switches.

2. A voltage regulator as set forth in claim 1, further characterized inthat the collector is constructed so the brush engaging it traverses allthe taps of the fine tap winding and while continuing its rotationaround the collector, holds the circuit closed while at least one ofsaid switches moves one step, the brush then continuing on in the samedirection of rotation for another cycle of step movements.

3. A voltage regulator of the type herein described utilizingtransformer windings, one having coarse taps and another having finetaps, interconnected by rotary switches with means for alternatelyoperating the switches from cont-act to contact, and a collector of thecommutator type having its bars connected to the transformer having thefine taps, a brush mounted for continuous rotation around the collector,the commutator connectiofisbeing such that the brush may be rotatedsuccessively around the collector in the same direction throughout theentire range of movement of said switches in one direction.

4. A voltage regulator as set forth in claim 3,

further characterized in that the brush will move continuously andsuccessively around the collcctor in the opposite direction when theregulator, including said switches, is operated in reverse directionfrom that set forth in claim 3.

5. A volt-age regulator as set forth in claim 3, further characterizedin that means are provided for stopping the regulator after the fullnumber of cycle steps have been completed in a given direction ofregulation.

6. A voltage regulator as set forth in claim 3, further characterized inthat the collector has at least a pair of bars of an arcuate length andpositioned at the end and beginning of the series of fine taps so therotating brush will remain on at least one of them while one of saidswitches is moving one step.

'7. A voltage regulator as set forth in claim 3, further characterizedin that the collector has at least a pair of bars of an arcuate lengthand positioned at the end and beginning of the series of fine taps sothe rotating brush will remain on at least one of them while one of saidswitches is moving one step, said pair of bars being adjacent each otherwhereby the rotating brush must make substantially a revolution aroundthe .collector before one of said switches moves a step.

8. A voltageregulator as set forth in claim 3, further characterized inthat the collector has at least a pair of bars of an arcuate length andpositioned at the end and beginning of the series of fine taps so therotating brush will remain on at least one of them while one of saidswitches is moving one step, said pair of bars being spacedapproximately 180 apart, where- A by the brush has to rotate onlyapproximately halfway around the collector to cover the range of finetaps. before the next switch is operated one step, the correspondingcommutator bar on opposite sides of said pair of bars being electricallycross-connected whereby the ,brush may continue its movement in the samedirection for the next cycle step.

9. A voltage regulator as set forth in claim 3, further characterized inthat the collector has at least a pair of bars of an arcuate length andpositioned at the end and beginning of the series of fine taps so therotating brush ,will remain on at least one of them while one of saidswitches is moving one step, said pair of bars being spacedapproximately 180 apart, whereby the brush has to rotate onlyapproximately halfway around the collector to cover the range of finetaps before the next switch is operated one step, a second fine taptransformer winding having the taps connected to complementary bars onthe opposite side of said pair of bars from the bars to which the finetaps from the first winding are connected.

10. A voltage regulator including a casing, and frame work, said framework comprising a pair of Geneva gears, a pair of rotary switchesoperated by said gears, a collector of the commutator type, a maintransformer having coarse taps connected to the switch "contacts, acollector transformer connected to said rotary switches and having finetaps therefrom, a drive shaft with means for operating it, a brushmounted for rotation around the collector by said shaft, said driveshaft being operatively connected to said Geneva gears, a slip ringcarried by said shaft, an auxiliary brush contacting with the slip ring,the ring and auxiliary brush serving to carry the current from thecollector brush to the load circuit, and special bars in the collectorinterconnected with the fine tap transformer, said special bars havingan arcuate length so the rotary brush can continuously move successivelyaround the collector as the switches are moved from step to step withoutopening the load circuit.

11. A voltage regulator as set forth in claim 10, further characterizedin that adjustable means are carried on the drive shaft for stopping theaction of the regulator at both ends of a cycle of movements of saidswitches.

12. A voltage regulator as set forth in claim 10, further characterizedin that said slip ring has a part carrying a stud on which saidcollector brush is mounted.

13. A voltage regulator as set forth in claim 10, further characterizedin that the special bars of the collector are locatedadjacently, onebeing connected to one end of the collector transformer winding and theother to the opposite end of said winding, the arcuate length of thebars being such as to allow the required switch movements to be madebefore the rotary brush leaves said special bars.

14. A voltage regulator as set forth in claim 10, further characterizedin that the special bars of the collector are located 180 apart andconnected one each to opposite ends of the collector transformer windingwhile complementary opposed bars are cross-connected, whereby the finetap winding is traversed twice by one rotation of the collector brush,said switches being actuated in steps when the rotary brush is on saidspecial bars.

15. A voltage regulator as set forth in claim 10, further characterizedin that the special bars of the collector are located 180 apart andconnected one each to opposite ends of the collector transformer windingwhile complementary opposed bars are connected to fine taps on anothertransformer winding which may be on the same transformer carrying thefirst-mentioned fine tap windings, whereby each fine tap winding istraversed by one rotation of the rotary brush, said switches beingactuated in steps when the rotary brush is on said special bars.

16. A voltage regulator as set forth in claim 10, further characterizedin that the special bars of the collector are located adjacently, onebeing connected to one end of the collector transformer winding and theother to the opposite end of said winding, the arcuate length of thebars being such as t6 allow the required switch movements to be madebefore the rotary brush leaves said special bars, the contacts of oneswitch being connected in order to the taps on the coarse tap windingbeginning with the first tap adjacent the starting end which isconnected to the first position contact on the other of said switches.

1'7. In a voltage regulator including; at least a pair of separatetransformer windings, one having coarse taps and the other fine taps,the coarse taps from one winding being interconnected to the otherwinding through a pair of independently operable switches with means foroperating the switches alternately in steps so the circuit between thewindings, including the load circuit,

that means are provided whereby the brush may be rotated continuously inthe same direction until the limit of movement of said switches in onedirection is reached, said means including a drive shaft carrying a slipring, an auxiliary brush serving to connect the rotary brush to the loadcircuit, said means further including special bars in the collectorconnected to the terminals of the fine tap winding and having an arcuatelength such that the switches may be operated from one step to anotherbefore the rotary brush leaves said special bars.

18. A voltage regulator as defined in claim 17, further characterized inthat said shaft carries adjustable means to automatically stop theregulater when the last step cycle in either direction of operation isreached.

19. A voltage regulator including a drive shaft, at least twoauto-transformers, one having coarse taps and another having fine taps,at least a pair of switches having contacts connected to the said coarsetaps and having their moving elements connected to said fine taps, themovable parts of the switches being operated from the drive shaft, acollector of the commutator type having its bars connected to the iinetaps, a brush mounted for operation is reached.

successive rotation around the collector in one direction according tothe action of the drive shaft, means for synchronizing the movement ofthe movable parts of said switches when said brush has traversed thefine tap winding in one direction, and means for stopping the regulatorwhen the full cycle of movement of the switches and said brush has beencompleted in either direction of regulation.

20. A voltage regulator as set forth in claim 1, further characterizedin that the collector is constructed so the brush engaging it traversesall the taps of the fine tap winding and while continuing its rotationaround the collector, holds the circuit closed while at least one ofsaid switches moves one step, the brush then continuing on in the samedirection of rotation for another cycle of step movements, andadjustable means for automatically stopping the regulator when the laststep cycle in either direction of ANDREW A. EMLEN. TAGE H. LUNDGREN.

